1. Field of the Invention
The present invention relates to production methods for a composite molded article comprising a composite wood overlay surface material and a synthetic resin. The production method of a composite molded article according to the present invention provides an excellent appearance of coating on the composite molded article by the production steps of firstly coating a wood veneer included in the composite wood overlay surface material, and then injecting the synthetic resin.
2. Description of the Related Art
Composite molded articles having grain patterns comprising a composite wood overlay surface material and a synthetic resin have been used widely in the interiors of cars, for furniture, and for electric appliances.
In order to produce composite molded articles having wood grain patterns, a composite wood sheet (such as a wood veneer backed by a sliced wooden veneer, a plywood, an unwoven fabric, or the like) as a surface material, has been employed in a production method comprising the steps of placing the surface material in a mold, injection-molding thereinto a synthetic resin which is to be a core material, and then coating the surface material.
The composite molded articles produced according to the aforementioned method are superior in appearance. However, when the form of the composite molded articles is complicated, inferior units are often produced due to the cracking of the surface material of the composite wood sheet.
In order to avoid the production of such inferior units, a method was developed comprising a step of placing, in a mold, a surface material composed of an aluminum sheet laminated on the back of the wood veneer. According to this method, the products have beautiful grain patterns and the production of inferior units can be avoided since the wood veneer is backed by the aluminum sheet. However, this method requires time and labor because the step of finish-coating on the curved surface of the composite molded article is not, amendable to automation of the coating step.